Field of the Invention
The disclosed and claimed concept relates to a leaf rake and, more specifically, to a leaf rake having two sets of tines with different contours.
Background Information
Leaf rakes are well known in the art. Leaf rakes include a handle and a head assembly. The head assembly includes a handle coupling, a base portion, and a number of tines. The base portion often has a planar triangular shape with the handle coupling disposed at the apex and a number of elongated tines extending from the base. The tines are structured to be flexible. That is, as used herein, a “tine” has an elongated body with a first end, a medial portion, and a second end. As used herein, a tine “medial portion” includes a flexure portion and an offset portion. A tine first end is coupled to, or unitary with, the base portion. A tine body “flexure portion” is structured to allow, and allows, the tine body to flex in, at least, a direction generally normal to the surface being raked. A tine body “offset portion” positions the distal second end out of the plane of the base portion. A tine second end is structured to engage the ground and to drag leaves and other debris.
Accordingly, as used herein, a tine “flexure portion” is that portion of a tine that has a longitudinal axis that is generally in, or generally parallel to, the plane of the base portion. As used herein, a tine “offset portion” is that portion of a tine that has a longitudinal axis that is not in, or generally parallel to, the plane of the base portion. As is known, a tine body may be generally curvilinear or may include a distinct bend. As used herein, and in a tine body that is generally curvilinear, the portion having a longitudinal axis that is within about 45 degrees of the plane of the base portion is the “flexure portion.” Conversely, in a tine body that is generally curvilinear the portion having a longitudinal axis that is more than about 45 degrees out of the plane of the base portion is the “offset portion.” As used herein, and in a tine body having a sharp bend, or “elbow,” the portion between the tine body first end and the bend is the “flexure portion.” Conversely, in a tine body having a sharp bend, the portion between the bend and the tine body second end is the “offset portion.” Further, as used herein, a tine body “second end” has a length of at least one-half inch. As tines are, generally, thinner than one-half inch, a tine second end has a longitudinal axis that is not generally in, or generally parallel to, the plane of the base portion.
Further, each tine body has a lateral cross-sectional aspect ratio. The lateral cross-sectional aspect ratio is determined relative to the minimal cross-sectional area at any location along the tine. Generally, the minimal cross-sectional area is determined by a plane that passes generally perpendicularly to the local longitudinal axis of the tine; that is, perpendicular to the longitudinal axis of the tine taken at a specific location. Generally, the lateral cross-sectional aspect ratio is determined by comparing a “width” to a perpendicular dimension. As used herein, the perpendicular dimension is identified as “length,” but, as detailed below this dimension is not always the dimension parallel to the handle longitudinal axis.
By way of example, a garden rake typically has a number of generally straight tines that extend generally perpendicular to the longitudinal axis of the handle. In this simple configuration, the “width” of a tine is measured in a direction generally perpendicular to the longitudinal axis of the handle and in a plane generally parallel to the plane of the base assembly. Conversely, the “length” of such a straight tine is measured in a direction generally parallel to the longitudinal axis of the handle and in a plane generally parallel to the plane of the base assembly.
The tines on a leaf rake, however, typically have a more complex shape and/or do not extend in a direction that is generally perpendicular to or parallel to the handle longitudinal axis. For example, a typical leaf rake has tines that extend in a generally radial pattern. That is, the outer tines are at a greater angle relative to the handle longitudinal axis than the center tines. Thus, if the tines have an identical cross-section, a plane that is perpendicular to the longitudinal axis of the handle passed through an outer tine would have a greater width than the same plane passed through a center tine. That is, the angle of the outer tine causes the plane that is perpendicular to the longitudinal axis to present a greater “width.”
Accordingly, it is understood that, as used herein for the purpose of determining a tine's “lateral cross-sectional aspect ratio,” the terms “width” and “length” are measured locally and generally correspond to a lateral “width” and “length” (which as noted above is the direction perpendicular to the width). Thus, to determine the “length” and “width” of a tine for the purpose of measuring an aspect ratio, the “length” and “width” are determined at a specific location along the tine by passing a plane through the tine so as to have a minimal cross-sectional area. The “width” is measured in the direction generally perpendicular to the longitudinal axis of the handle and in a plane generally parallel to the plane of the base assembly. By way of example, in a leaf rake with tines that extend in a generally radial pattern, the “width” of a center tine that is aligned with the longitudinal axis of the handle is the dimension measured in the direction substantially perpendicular to the longitudinal axis of the handle and in a plane generally parallel to the plane of the base assembly. Conversely, the “width” of an outermost tine that is offset from the handle longitudinal axis by about 20 degrees, is the dimension measured in the direction about 20 degrees to the longitudinal axis of the handle and in a plane generally parallel to the plane of the base assembly. It is understood that if the tines have a similar shape and contour, the aspect ratio for the tines is similar and can be easily determined at the centermost tine.
It is noted that the aspect ratio relevant to the disclosed and claimed concept is the aspect ratio of the portion of the tines close to the tips and, as such, the “length,” as used herein, is generally parallel to the longitudinal axis of the handle when measured at the tine tips. It is noted that the dimension of a tine perpendicular to the “width” when measured adjacent to the head assembly base portion would more typically be described as a “height” using the convention of length, width and height. But, as noted above, when determining a tine lateral cross-sectional aspect ratio, the dimension perpendicular to the “width” is identified herein as a “length.”
Thus, a line's lateral cross-sectional aspect ratio is the “width” divided by the “length.” In a leaf rake, the lateral cross-sectional aspect ratio for the tines is greater than 1.0. Thus, at the distal tips of the tines, the tines are wider in the lateral direction than in the direction generally parallel to the handle longitudinal axis. As another example, a generally circular wire tine has a lateral cross-sectional aspect ratio of about 1.0. That is, a body with a generally circular cross-section is about as wide as it is long. It is noted that some tines (or thatching rake blades, discussed below) may include sharpened points; as used herein, the “lateral cross-sectional aspect ratio” is based on the entire tine, the entire blade or for an identified portion thereof. For example, the “offset portion” lateral cross-sectional aspect ratio is based on the cross-sectional aspect ratio of the entire “offset portion” of a tine and not the aspect ratio at a specific elevation on the offset portion and particularly not at the distal tip.
A leaf rake is structured to remove leaves and debris from the surface of the ground. The ground may include a layer of thatch; a leaf rake is not structured to lift thatch. A leaf rake generally has tines with a lateral cross-sectional aspect ratio that is greater than 1.0. In this configuration, the wide tines are structured to present a wide face to the leaves and debris that are being dragged. That is, tines with a lateral cross-sectional aspect ratio that is greater than 1.0 are wide and therefore have a greater surface area perpendicular to the direction that the tines are moved. Further, the purpose of the leaf rake is to move over the surface being raked. The flexible tines allow this purpose to be accomplished. It is noted that if the tines of a leaf rake were too rigid, then the leaf rake tines would be unsatisfactory for their intended purpose; that is, the tines would bite into the ground.
A garden rake is structured to loosen soil, perform light weeding and to level loose soil. A garden rake may be used to remove thatch as well. The tines of a garden rake are generally shorter than on a leaf rake and typically include only an offset portion extending from a transverse support bar. Further, a garden rake tine has a lateral cross-sectional aspect ratio of about 1.0. That is, a garden rake tine typically has a generally circular or generally square cross-sectional shape. A garden rake tine generally has a cross-sectional area that is larger than a leaf rake. Thus, garden rake tines are short and thick and therefore rigid. Such rigid tines allow the garden rake to bite into the ground or into thatch. It is noted that if a garden rake tine was flexible, or flexibly coupled to the handle, then the tine would be unsatisfactory for its intended purpose; it would not bite into the ground.
A thatching rake is structured to remove thatch. That is, a thatching rake is structured to bite, or dig slightly, into the ground or at least into the layer of thatch that is over the dirt. A thatching rake does not have “tines” as defined herein; rather, a thatching rake includes a number of “blades.” As used herein, the “blades” of a thatching rake are planar members disposed in a parallel configuration and have a lateral cross-sectional longitudinal aspect ratio that is generally, or substantially, less than 1.0.
In this configuration, i.e. when the blade's lateral cross-sectional aspect ratio that is generally less than 1.0, the thatching rake blade is substantially rigid. This rigidity is required for the thatching rake blades to bite into and lift the thatch. It is noted that if a thatching rake blade was flexible, or flexibly coupled to the handle, then the blade would be unsatisfactory for its intended purpose; it would not bite into and lift the thatch.
A disadvantage of leaf rakes is that the flexible tines allow heavy debris, such as but not limited to wet leaves, to pass under the tines. There is, therefore, a need for a leaf rake that is able to move heavy leaves and debris over the surface of the ground.
Further, leaf rakes are wide, typically over 18 inches at the widest point. Leaf rakes with such a width are difficult to use in locations where trees and shrubs are clustered. To reach such areas, leaf rakes are constructed with a smaller width. The disadvantage to this is that a user must carry two leaf rakes; one for use in open spaces and one or use between shrubs, there is, therefore a need for a rake assembly that is structured to operate on both open and narrow areas.